#include "stdio.h"
void main()
{
float score;
char grade;
printf("請輸入學生成績：");
scanf("%f",&score);
while(score>100||score<0)
{
printf("輸入有誤，請重輸：");
scanf("%f",&score);
}
switch((int)(score/100))
{
case 10:grade='A';break;
case 9:grade='A';break;
case 8:grade='B';break;
case 7:grade='C';break;
case 6:grade='D';break;
default:grade='E';
}
printf("成績是%5.1f,相應的等級是%c\n",score,grade);
}